1. Field of the Invention
The present invention relates to database migration in a database management system (DBMS) and more particularly to the evaluation of the performance of a database when migrating the database from one DBMS system to another.
2. Description of the Related Art
One of the most valuable assets that any organization has is the data that the organization accumulates as a result of its operations. Presently, an organization stores its data in a DBMS. A DBMS is a computer program (or in reality, a set of computer programs) that allows one or more computer users to create and access data in a database The DBMS manages user data requests and data requests from other computer programs so that users and other computer programs are free from having to understand where the data is physically located on storage media and, in a multi-user system, who else may also be accessing the data. Further, in handling user requests, the DBMS ensures the integrity of the data and the security of the data.
The choice of a particular DBMS is important. When an organization considers migrating an existing data warehouse from a existing DBMS to a different DBMS, a main consideration is the relative performance of the data warehouse after the migration. Indeed, this may be one of the key drivers behind the exchange of the existing DBMS to the new DBMS.
The databases managed by a DBMS typically are directed either to transaction processing or query and analysis. The latter type of database often is referred to as a data warehouse. Data warehouse systems are by definition extremely large and a full data migration of a data warehouse is usually a complex and time consuming process. The effort and duration required to perform the migration of the data warehouse in order to test the performance of a new replacement DBMS is generally well beyond the scope of the mere selection of the new DBMS. What is required is a facility to quantifiably predict the performance of a data warehouse system post-migration to the new DBMS, quickly and without actually migrating any data.
Efforts to compare the performance of rival DBMS systems have been made by others. Traditionally, these efforts involve populating a benchmark workload such as those provided by the Transaction Processing Performance Council, on each of the respective DBMS systems and comparing the performance of each. Naturally, this is a time-consuming activity and assumes that sufficient system resources including storage is available for each DBMS. Analogously, the current state-of-the-art provides techniques for preserving and validating query execution plans during the migration to another DBMS. Another contemporary performance evaluation method considers the prediction of the performance of a given DBMS under different workload and hardware configurations in order to provide for future capacity planning. However, the state of the art does not provide a solution for the accurate and quantifiable prediction of system performance on a replacement DBMS without migrating data, in order to make a reliable comparison with the existing DBMS before proceeding with its replacement.